Modern farming techniques require extensive use of irrigation to maximum crop yields. A particularly prevalent and important irrigation method involves the use of irrigation pipe sections, normally of aluminum tubing that are approximately 30' in length and which each mount a single sprinkler head. Each sprinkler head is sufficient to irrigate an area approximately 30' to 40' from the sprinkler head. The pipe sections incorporate a flange to cause the sprinkler riser to stand upright on the ground. Sections are connected by joint couplings. In one prevalent type, the joint coupling comprises a male/female coupling that is assembled by inserting the male end at an angle into the female coupling and then bringing the pipe sections into alignment.
In order to make maximum use of irrigation piping it is moved from field to field as the need for irrigation changes. According to conventional practice, the pipe is manually assembled and disassembled. In picking up pipe, for example, workers lift one end of a pipe section to angulate it relative to the attached section and then withdraw the male end of the coupling from the female coupling, carry the section over several rows of growing crops to a trailer towed through the field by a tractor or the like, load the pipe onto the trailer and return over the several rows of crops to pick up the next section. Since the workers must walk a considerable distance away from the tractor to retrieve each section, the distance they travel through the fields is many times greater than the length of pipe being retrieved. Filled trailers are towed to the next field to be irrigated where workers laying pipe must await its arrival. The pipe is layed in substantially the reverse manner as it is picked up necessitating the same amount of walking and manual assembly of the pipe sections. The vehicle and driver utilized for towing filled trailers between fields is idle a substantial part of the time waiting for additional trailers to be filled.
Therefore, it is desirable to have a vehicle specifically designed for picking up and laying irrigation pipe which reduces the manpower and equipment required to accomplish the task and to transfer the pipe to another location. Previously suggested designs for such a vehicle have resulted in highly complex apparatus for grasping, angulating, disconnecting, lifting and stacking each pipe section. Such vehicles have a large number of grasping and manipulating mechanisms and the associated hydraulic or other actuators and, as a result, no practical device for picking up and laying irrigation pipe has been successfully manufactured. Such machinery requires a high degree of operator skill and a high level of required maintanance while still producing unacceptable low reliability.